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11.
INVOLVEMENT OF NON-NMDA AND NMDA RECEPTORS IN GLUTAMATE-INDUCED PRESSOR OR DEPRESSOR RESPONSES OF THE PONS AND MEDULLA 总被引:1,自引:0,他引:1
SY Chen WC Wu CJ Tseng JS Kuo CY Chai 《Clinical and experimental pharmacology & physiology》1997,24(1):46-56
1. Fifty-five intact and six baroreceptor denervated and vagotomized cats of either sex were anaesthetized intraperito-neally with urethane (400 mg/kg) and a-chloralose (40 mg/kg). Responses of the systemic arterial pressure (SAP), mean SAP (MSAP) and sympathetic vertebral nerve (VNA) and renal nerve activities (RNA) were recorded. 2. In intact animals, monosodium L-glutamate (Glu, 0.1 mol/L, 50 nL) was microinjected into pressor areas of the locus coeruleus (LC), gigantocellular tegmental field (GTF), rostral ventrolateral medulla (RVLM) and dorsomedial medulla (DM), and the depressor areas of caudal ventrolateral medulla (CVLM). The induced actions were compared before and after microinjection of either glutamate antagonists, glutamate diethylester (GDEE, 0.5 mol/L, 50–100nL), a competitive AMPA receptor blocker, or 2-amino-5-phosphonovaleric acid (D-AP5, 0.025 mol/L, 50–100 nL), a competitive N-methyl-D-aspartate (NMDA) receptor blocker. GDEE completely blocked the increases of SAP and VNA elicited from all pressor areas. D-AP5 only partially blocked the pressor but slightly blocked VNA and RNA responses from LC, GTF and DM, particularly those from RVLM. Neither GDEE nor D-AP5 blocked the depressor responses of SAP and two nerve activities elicited from CVLM. 3. In baroreceptor denervated animals, NMDA (2 mmol/L, 50–100 nL) and AMPA (0.2 mmol/L, 50–100 nL) were micro-injected into the same pressor areas of GTF, RVLM and DM and the depressor area of CVLM responsive to Glu activation (0.1 mol/L, 30 nL). In RVLM, DM and CVLM, the results of either NMDA or AMPA were similar to those induced by Glu. However, in GTF, microinjection of either NMDA or AMPA did not induce similar responses to Glu. This suggests that the nature of GTF may differ from RVLM and DM. 4. The above results suggest that the Glu-induced pressor responses from LC, GTF, DM and especially RVLM, are primarily mediated through AMPA receptors. The Glu-induced depressor responses from CVLM may not be predominantly mediated by either AMPA or NMDA receptors. 5. In both baroreceptor-intact and -denervated cats stimulation of the pressor areas often produced an increase of VNA and a decrease of RNA, while in the depressor CVLM decreased both VNA and RNA. The VNA, but not RNA were positively correlated with the pressor responses, while both VNA and RNA were positively correlated with the depressor responses. This may suggest that neurons of the sympathetic vertebral and renal nerves are topographically organized in the brain. 相似文献
12.
OBJECTIVES: To investigate variation among neonatal intensive care units (NICUs) in prevalence and management of thrombocytopenia in infants <1500 g. STUDY DESIGN: In total 1283 infants &<1500 g admitted to six NICUs over 21 months were prospectively analyzed. Illness severity was measured by the Score for Neonatal Acute Physiology (SNAP). Platelet counts in the first 12 hours after birth and on day 3 of life were abstracted from the infants' medical records. Thrombocytopenia was determined from the lowest platelet count in each of these time periods. RESULTS: There was variability in rates of thrombocytopenia among NICUs, even after controlling for risk factors (e.g., SNAP, small for gestational (SGA) age and maternal hypertension). One site had a high prevalence of thrombocytopenia, but the lowest percentage of infants with thrombocytopenia who received platelet transfusions. After controlling for SNAP, GA, SGA, Apgar score and incidence of thrombocytopenia, the odds of receiving platelets at this site, relative to the site with the highest transfusion rate, was 0.10 (95% CI 0.02 to 0.43). CONCLUSIONS: This multicenter study finds a 10-fold variation among NICU in the administration of platelets to their thrombocytopenic infants that cannot be explained by presence of thrombocytopenia or illness severity. 相似文献
13.
Objective: To develop and evaluate the psychometric properties (reliability, validity etc.) of a comprehensive Quality of Life (QOL) tool, for patients infected with the human immunodeficiency virus (HIV), that was adapted from a previously validated cancer tool. Design: Cross-sectional, patient completed written surveys and interviews. Setting: The Medical Centers serving HIV infected patients in the Los Angeles community including UCLA, community physicians, Veterans Affairs Medical Centers, and a County hospital: and additional data contributed from Johns Hopkins University Medical Center CMV Retinitis Clinic. Patients: Patients (n=318) with HIV infection including asymptomatic (37%), ARC (20%), AIDS (25%) and AIDS with Cancer (18%) receiving health services at one of the above sites. Measurements: The patients self-administered the newly developed instrument, the HOPES (HIVOverview ofProblems-EvaluationSystem), other QOL related tools including the Medical Outcomes Study instrument adapted for HIV (MOS-HIV) the Profile of Mood States (POMS), the Perceived Adjustment to Chronic Illness Scale (PACIS), and the Physical Activity Scale (PAS). Brief interview to assess the Karnofsky Performance Status Score (KPS). Measured sociodemographic characteristics included age, sex, race, HIV risk factor, education etc. Assessed medical history, current medications, HIV clinical classification. Main results: The sociodemographic and medical characteristics of the sample resemble those of the general population with HIV infection in this geographic area: 96% male, 28% nonwhite, 84% homosexual contact as risk factor, 75% receiving antiretroviral therapy. The adaptation of the cancer QOL instrument to HIV appears to have face and content validity according to patients and health professionals who care for HIV infected patients. Analyses of the psychometric properties found that the HOPES has a similar structure to its parent instrument following factor analyses which results in five summary scales representing the Physical, Psychosocial, Medical Interaction, Sexual and Significant Other/Partners domains in addition to a Global Score. Internal consistency of 35 subscales is high with a mean alpha coefficient of 0.82. Correlations of the HOPES summary scales with other QOL instruments are in the predicted directions. Comparing patients within the HIV clinical diagnostic categories on the HOPES Global, Physical, and Psychosocial Summary Scales indicates that Asymptomatic Patients have better QOL than symptomatic patients. This finding is also found in the other QOL instruments which provides evidence of construct validity. Conclusions: The HOPES is an excellent tool for identifying the problems and needs of patients with HIV infection and for assessing their quality of life. It is reliable, valid and acceptable to patients. The tool may be especially useful in developing a normative data base.This paper is dedicated to the memory of Jimmy Stophel who died of AIDS and whose sense of humour improved the quality of many people's lives.This research was supported in part by the UCLA AIDS Clinical Research Center and CARES Consultants. To obtain information about the HOPES, please contact C. A. Coscarelli Schag, CARES Consultants, 2210 Wilshire Blvd., Suite 359, Santa Monica, CA 90403, USA. 相似文献
14.
Hillmann JS; Mesgarzadeh M; Revesz G; Bonakdarpour A; Clancy M; Betz RR 《Radiology》1987,165(3):769-773
Proximal femoral focal deficiency, an uncommon congenital anomaly, necessitates early radiologic classification for surgical planning and treatment. Objective radiographic criteria, including femoral length index, acetabular depth index, acetabular angle index, and shape of the proximal femur were determined in 49 patients before cartilaginous ossification of the femoral capital epiphysis; final classification was based on follow-up radiographs or findings at arthrography or surgery. These parameters were analyzed to determine the accuracy and contributions of each in classification. Correct classification into one of three groups was possible in 86% of cases with use of three of the parameters: femoral length index, acetabular depth index, and shape of the proximal femur. The acetabular angle was found to contribute insignificantly to classification. Magnetic resonance imaging, used in only one case, depicted the nonossified cartilaginous femoral capital epiphysis, thus obviating the need for invasive diagnostic procedures and facilitating early classification. 相似文献
15.
Photosensitivity and photodermatitis in childhood 总被引:1,自引:0,他引:1
G Kahn 《Dermatologic Clinics》1986,4(1):107-116
Photosensitivity disorders of children are uncommon, except for banal overexposure reactions to sunlight. Although the long-term sequelae of chronic or intense sun exposure are not often seen in children, physicians should advise patients of the harmful effects and irreversible skin damage that results from unduly prolonged sun exposure. Damage accumulates over the years to cause premature aging, senile elastosis, actinic keratoses, and squamous- and basal-cell carcinomas. Besides the pigmentary changes, wrinkles, and skin cancers--genuine sources of altered appearance and morbidity--we now know that sunburned children develop a higher incidence of melanoma, which is not a rare cause of death in young adults. In Australia, where the incidence of melanoma is highest, a strong correlation exists for melanoma in children who get sunburn before the age of 10. Also, the incidence of melanoma is 50 times as great in bikini wearers who get sunburn as in girls who wear one-piece bathing suits. 相似文献
16.
Characterization of binding and phosphorylation defects of erythrocyte insulin receptors in the type A syndrome of insulin resistance 总被引:7,自引:0,他引:7
The type A syndrome of insulin resistance and acanthosis nigricans is characterized by severe insulin resistance due to a cellular defect in insulin action. To better understand the molecular nature of this defect, we have investigated insulin binding to circulating monocytes, erythrocytes, and the Triton X-100-solubilized erythrocyte receptor, and insulin-stimulated receptor autophosphorylation using cells and receptor from three type A patients. Insulin binding in both circulating cells and the soluble extract of erythrocytes indicated a heterogeneity of defects. Patients A1 and A2 both presented a major decrease in tracer insulin binding to intact cells and soluble insulin receptor. Determination of stoichiometric binding parameters using a cooperative model indicated that in patient A1 this was due to a reduction in the number of receptors, whereas in patient A2 the affinity constant for binding was decreased. Patient A3 presented near-normal insulin binding to erythrocytes and normal binding in intact monocytes, solubilized erythrocyte receptors, and cultured fibroblasts. Affinity labeling of erythrocyte receptor from this patient revealed a normal alpha-subunit and also a normal relative distribution of the higher-molecular-weight, nonreduced oligomeric forms of the receptor. Receptor autophosphorylation was measured using the solubilized insulin receptor from erythrocytes. The maximal stimulated phosphorylation was reduced by 79%, 76%, and 52% in patients A1, A2, and A3, respectively, relative to the simultaneous control. In all three patients, the autophosphorylation was stimulated only 1.0-3.5 times the basal level compared with controls, in which the stimulation was 5.7-fold +/- 1.2 (mean +/- 1 SD, P less than 0.005). In addition, in patients A1 and A2 a decrease in basal phosphorylation was observed and in patient A2 there was a rightward shift of the dose-response curve for insulin stimulation. These data and the correlation of coupling of receptor phosphorylation with the fractional occupancy of the receptor measured in the same extract suggest that these patients exhibit three types of defects. In patient A1, there is a loss in receptor number manifested by a parallel decrease in insulin binding and receptor phosphorylation. In patient A2, there is an additional decrease in the affinity constant leading to a decrease in both binding and receptor phosphorylation with an almost linear coupling between receptor occupancy and receptor phosphorylation.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
17.
This study investigated the relationship between increased serotonin (5-hydroxytryptamine, 5HT) receptor sensitivity and human aggression. A low oral dose of meta-chlorophenylpiperazine (MCPP), a postsynaptic 5HT receptor agonist, was administered in a placebo-controlled design to depressed (n = 22) and panic disorder (n = 20) patients classified with or without signs of outwardly directed aggression, patients with a history of suicide attempts (inwardly directed aggression) (n = 11), and normal controls (n = 19). Hormones under 5HT control were measured at 30-min intervals. Results were as follows: (1) MCPP did not induce or reduce anger, (2) patients with outwardly directed aggression did not have significantly greater MCPP-induced cortisol or prolactin release than did patients without signs of outwardly directed aggression, (3) patients with a history of suicide attempts did not have significantly greater MCPP-induced cortisol or prolactin release than did normal controls, and (4) MCPP-induced hormone release was unrelated to measures of aggression. 相似文献
18.
M E Weinblatt E Kahn P G Scimeca J A Kochen 《The American journal of pediatric hematology/oncology》1987,9(4):295-298
An adolescent with a small round cell tumor of the chest wall, who was treated with cisplatin, developed hemolytic uremic syndrome with severe hypertension, which ultimately contributed to her death. Cisplatin's role as a possible causative agent of this syndrome is discussed. Recommendations are made for monitoring abnormalities that may signal the onset of this potential complication. 相似文献
19.
Hodgkin's disease (HD) was diagnosed in 24 patients who were either seropositive for human immunodeficiency virus (HIV) (21) or members of a high-risk group (three), but had not developed acquired immune deficiency syndrome (AIDS). Clinical presentation of the disease was characterized by constitutional symptoms in all, especially fever (23/24) and disseminated disease (22/24) at diagnosis. Mediastinal adenopathy was rare. Bone marrow involvement was particularly frequent (12/24), and a positive bone marrow biopsy preceded lymph node biopsy in 5 of the 12. Histopathologic features of these tumors included an increased number of nonlymphoid stromal cells, i.e., histiocytic and/or fibroblastoid. In some tumors these fibrohistiocytoid stromal cells were arranged in bundles, but distinct nodule with birefringent collagen band formation was not observed. Twenty-two patients were treated, most with combination chemotherapy; one was untreated; one, unknown. Sixteen, including the one untreated, died with disease at 3 to 25 months; one died of an unrelated cause; four were alive at 3 to 24 months; three were lost to follow-up. Frequent bone marrow involvement at presentation suggests the usefulness of the bone marrow biopsy for diagnosis in subjects at risk, especially when they present with spiking fever of unknown origin. Contrary to most previous series, virtually all of our cases were of mixed cellularity type, characterized by increased fibrohistiocytoid stromal cells in place of depleting lymphocytes. The classic nodular sclerosing feature with birefringent collagen band formation was not observed. In conclusion, HIV-associated HD was characterized by advanced stage with fever at presentation, preponderance of mixed cellularity histologic type with increased fibrohistiocytoid stromal cells, and poor outcome. Hodgkin's disease in AIDS patients presents an intriguing biological model to study the role of stromal histiocytes in immunodeficient patients. 相似文献
20.